:root {
  --paper: #fafffa;
  --ink: #121613;
  --ink-soft: #232924;
  --muted: #516254;
  --faint: #91a194;
  --line: #c8d2c8;
  --green: #2bee4b;
  --green-deep: #18a23a;
  --green-soft: rgba(43, 238, 75, 0.16);
  --dark-card: #1a221c;
  --dark-line: #2e362f;
  --dark-text: #e9f2ea;
  --font-display: "Instrument Serif", "Noto Serif SC", "Songti SC", serif;
  --font-body: "Noto Sans SC", -apple-system, "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-mono: "Space Mono", ui-monospace, "JetBrains Mono", monospace;
}
* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 15.5px;
  line-height: 1.75;
}
::selection { background: var(--green); color: var(--ink); }
code, .mono { font-family: var(--font-mono); font-size: 0.92em; }
a { color: var(--ink); text-decoration: underline; text-decoration-color: var(--green); text-underline-offset: 3px; }
a:hover { background: var(--green-soft); }

/* ---------- nav ---------- */
nav {
  position: sticky; top: 0; z-index: 50;
  backdrop-filter: blur(10px);
  background: rgba(250, 255, 250, 0.88);
  border-bottom: 1px solid var(--ink);
}
.nav-inner {
  max-width: 1200px; margin: 0 auto; padding: 0 24px;
  display: flex; align-items: center; gap: 20px; height: 58px;
}
.logo {
  font-family: var(--font-display); font-size: 18px; letter-spacing: 0.5px;
  white-space: nowrap; font-weight: 400;
}
.logo b { color: var(--green-deep); font-weight: 400; }
.nav-links { display: flex; gap: 2px; overflow-x: auto; scrollbar-width: none; margin-left: auto; }
.nav-links::-webkit-scrollbar { display: none; }
.nav-links a {
  color: var(--muted); font-family: var(--font-mono); font-size: 11.5px;
  letter-spacing: 0.1em; text-transform: uppercase; white-space: nowrap;
  text-decoration: none; padding: 4px 9px;
}
.nav-links a:hover { color: var(--ink); background: var(--green-soft); }
.lang {
  flex: none; font-family: var(--font-mono); font-size: 11.5px; font-weight: 700;
  letter-spacing: 0.08em; text-decoration: none; white-space: nowrap;
  border: 1px solid var(--ink); background: var(--green); color: var(--ink);
  padding: 4px 12px; transition: background .15s, color .15s;
}
.lang:hover { background: var(--ink); color: var(--green); }

/* ---------- layout ---------- */
section { max-width: 1200px; margin: 0 auto; padding: 0 24px; scroll-margin-top: 74px; }
.sec-head {
  border-top: 1px solid var(--ink);
  margin-top: 80px; padding-top: 14px;
  display: flex; align-items: baseline; justify-content: space-between; gap: 16px;
}
.kicker {
  font-family: var(--font-mono); color: var(--ink); font-size: 11.5px;
  letter-spacing: 0.16em; text-transform: uppercase;
}
.kicker .no { color: var(--green-deep); }
h2 {
  font-family: var(--font-display); font-weight: 400;
  font-size: clamp(26px, 3.2vw, 38px); line-height: 1.22;
  margin: 14px 0 10px;
}
.lead { color: var(--muted); max-width: 780px; margin-bottom: 32px; font-size: 15px; }

/* ---------- dark band ---------- */
.band { background: var(--ink); color: var(--dark-text); margin-top: 80px; padding: 8px 0 72px; }
.band section { scroll-margin-top: 74px; }
.band .sec-head { border-top-color: var(--dark-line); margin-top: 64px; }
.band .kicker { color: var(--dark-text); }
.band .kicker .no { color: var(--green); }
.band .lead { color: var(--faint); }
.band a { color: var(--dark-text); }

/* ---------- hero ---------- */
.hero { padding: 68px 24px 52px; position: relative; }
.hero-tag {
  font-family: var(--font-mono); font-size: 11.5px; letter-spacing: 0.18em;
  text-transform: uppercase; color: var(--muted); margin-bottom: 26px;
  display: flex; align-items: center; gap: 12px;
}
.hero-tag::before { content: ""; width: 8px; height: 8px; background: var(--green); display: inline-block; }
.hero h1 {
  font-family: var(--font-display); font-weight: 400;
  font-size: clamp(32px, 4.6vw, 58px); line-height: 1.16;
  letter-spacing: -0.01em; max-width: 1000px;
}
.hero h1 .em {
  font-style: italic;
  background: linear-gradient(transparent 74%, var(--green) 74%, var(--green) 94%, transparent 94%);
}
.hero p.sub { color: var(--muted); font-size: 15.5px; max-width: 720px; margin-top: 26px; }
.facts-strip {
  display: flex; flex-wrap: wrap; margin-top: 44px;
  border-top: 1px solid var(--ink); border-bottom: 1px solid var(--ink);
}
.facts-strip .f {
  flex: 1 1 200px; padding: 14px 18px 13px; border-right: 1px solid var(--line);
}
.facts-strip .f:last-child { border-right: none; }
.facts-strip .f .v { font-family: var(--font-display); font-size: 28px; line-height: 1; }
.facts-strip .f .k { font-family: var(--font-mono); font-size: 10.5px; letter-spacing: 0.08em; text-transform: uppercase; color: var(--muted); margin-top: 7px; }

/* ---------- marquee ---------- */
.marquee {
  overflow: hidden; background: var(--ink); color: var(--paper);
  border-top: 1px solid var(--ink); border-bottom: 1px solid var(--ink);
  padding: 13px 0;
}
.marquee.green { background: var(--green); color: var(--ink); }
.marquee.mt-band { margin-top: 80px; }
.marquee-track {
  display: inline-flex; white-space: nowrap;
  animation: marquee 42s linear infinite;
}
.marquee-track > span {
  font-family: var(--font-display); font-size: clamp(20px, 2.4vw, 30px);
  line-height: 1.2; padding-right: 0.6em;
}
.marquee .sep { color: var(--green); font-style: normal; }
.marquee.green .sep { color: var(--paper); }
.marquee em { font-style: italic; }
@keyframes marquee { to { transform: translateX(-50%); } }
@media (prefers-reduced-motion: reduce) { .marquee-track { animation: none; } }

/* ---------- cards ---------- */
.grid { display: grid; gap: 0; border: 1px solid var(--ink); }
.g3 { grid-template-columns: repeat(3, 1fr); }
.g2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 880px) { .g3, .g2 { grid-template-columns: 1fr; } }
.card {
  background: #fff; border-right: 1px solid var(--line); border-bottom: 1px solid var(--line);
  padding: 26px 24px; transition: background .15s;
}
.card:hover { background: var(--paper); box-shadow: inset 0 3px 0 var(--green); }
.card h3 { font-family: var(--font-display); font-weight: 400; font-size: 19.5px; line-height: 1.32; margin-bottom: 10px; }
.card p { color: var(--muted); font-size: 14px; }
.card .idx { font-family: var(--font-mono); font-size: 11px; color: var(--green-deep); letter-spacing: 0.14em; display: block; margin-bottom: 12px; }
.tag {
  display: inline-block; font-family: var(--font-mono); font-size: 10.5px; font-weight: 400;
  letter-spacing: 0.07em; text-transform: uppercase;
  border: 1px solid var(--ink); padding: 2px 9px; margin: 0 6px 10px 0;
}
.t-purple { border-color: var(--ink); color: var(--ink); }
.t-green  { border-color: var(--green-deep); color: var(--green-deep); }
.t-cyan   { border-color: var(--faint); color: var(--muted); }
.t-orange { border-color: var(--ink); background: var(--green); color: var(--ink); }
.facts { margin-top: 14px; border-top: 1px dashed var(--line); padding-top: 11px; }
.facts li { list-style: none; color: var(--muted); font-size: 13px; padding: 2px 0; }
.facts li::before { content: "→ "; color: var(--green-deep); font-family: var(--font-mono); }

/* ---------- mermaid blocks (dark band) ---------- */
.diagram {
  background: var(--dark-card); border: 1px solid var(--dark-line);
  padding: 24px; margin-bottom: 22px; overflow-x: auto;
}
.diagram h3 { font-family: var(--font-display); font-weight: 400; font-size: 18px; margin-bottom: 5px; }
.diagram h3 .no { font-family: var(--font-mono); font-size: 11.5px; color: var(--green); letter-spacing: 0.1em; margin-right: 10px; }
.diagram .note { color: var(--faint); font-size: 13px; margin-bottom: 14px; }
.mermaid { display: flex; justify-content: center; }
.mermaid svg { max-width: 100%; height: auto; }
/* Subgraph titles are lifted above edge paths by app.js; give them an opaque
   chip so any edge passing underneath stays clear of the text. */
.mermaid .cluster-label span,
.mermaid .cluster-label div { background: #161c17; padding: 1px 10px; border: 1px solid var(--dark-line); color: #c8d2c8; }
/* On small screens, keep diagrams at a readable width and scroll horizontally
   instead of shrinking them to fit. */
@media (max-width: 720px) {
  .mermaid { justify-content: flex-start; }
  .mermaid svg { min-width: 560px; }
}

/* ---------- charts & demo ---------- */
.panel { background: #fff; border: 1px solid var(--ink); padding: 24px; }
.panel h3 { font-family: var(--font-display); font-weight: 400; font-size: 18.5px; margin-bottom: 4px; }
.panel .note { color: var(--muted); font-size: 13px; margin-bottom: 14px; }
.chart-wrap { position: relative; height: 280px; }
.grid.charts { border: none; gap: 16px; margin-bottom: 16px; }
.btn-row { display: flex; gap: 10px; flex-wrap: wrap; }
button.btn {
  font-family: var(--font-mono); font-size: 12px; font-weight: 700;
  letter-spacing: 0.06em; text-transform: uppercase; cursor: pointer;
  border: 1px solid var(--ink); padding: 9px 20px;
  background: var(--green); color: var(--ink); transition: background .15s, color .15s;
}
button.btn:hover { background: var(--ink); color: var(--green); }
button.btn.alt { background: transparent; color: var(--ink); }
button.btn.alt:hover { background: var(--ink); color: var(--paper); }
button.btn.ghost { background: transparent; border-color: var(--line); color: var(--muted); }
button.btn.ghost:hover { background: var(--paper); color: var(--ink); border-color: var(--ink); }
button.btn:disabled { opacity: 0.35; cursor: not-allowed; }
.stack-viz { display: flex; flex-direction: column-reverse; gap: 5px; min-height: 170px; justify-content: flex-start; margin: 16px 0; }
.stack-item {
  padding: 5px 12px; font-family: var(--font-mono); font-size: 12px;
  background: var(--green-soft); border: 1px solid var(--ink);
  animation: pop-in .25s ease;
}
.stack-item.base { background: transparent; border: 1px dashed var(--line); color: var(--muted); }
@keyframes pop-in { from { transform: translateY(-8px); opacity: 0; } to { transform: none; opacity: 1; } }
.stat-row { display: flex; flex-wrap: wrap; gap: 0; margin-top: 10px; border: 1px solid var(--ink); }
.stat { flex: 1 1 150px; background: #fff; border-right: 1px solid var(--line); padding: 10px 16px; }
.stat:last-child { border-right: none; }
.stat .v { font-family: var(--font-display); font-size: 17.5px; line-height: 1.25; }
.stat .k { font-family: var(--font-mono); font-size: 10px; letter-spacing: 0.05em; text-transform: uppercase; color: var(--muted); margin-top: 4px; }
.ok { color: var(--green-deep); }

/* ---------- highlights (dark band) ---------- */
.band .grid { border-color: var(--dark-line); }
.band .card { background: transparent; border-color: var(--dark-line); }
.band .card:hover { background: var(--dark-card); box-shadow: inset 0 3px 0 var(--green); }
.band .card h3 { color: var(--dark-text); font-size: 18.5px; }
.band .card p { color: var(--faint); }
.hl { display: flex; gap: 18px; }
.hl .num {
  flex: none; font-family: var(--font-display); font-style: italic;
  font-size: 30px; line-height: 1.1; color: var(--green); min-width: 32px;
}

/* ---------- issues ---------- */
.issue { display: flex; gap: 16px; align-items: flex-start; padding: 17px 0; border-bottom: 1px solid var(--line); }
.issue:last-child { border-bottom: none; }
.sev {
  flex: none; font-family: var(--font-mono); font-size: 10.5px; font-weight: 700;
  letter-spacing: 0.1em; text-transform: uppercase;
  padding: 3px 10px; margin-top: 4px; border: 1px solid;
}
.sev.high { color: #c43c2e; border-color: #c43c2e; }
.sev.med  { color: #a06a1f; border-color: #a06a1f; }
.sev.low  { color: var(--muted); border-color: var(--faint); }
.sev.fixed { color: var(--green-deep); border-color: var(--green-deep); }
.sev.idx  { color: var(--ink); border-color: var(--ink); }
.issue h4 { font-size: 15px; font-weight: 700; }
.issue p { color: var(--muted); font-size: 13.5px; }

/* ---------- ecosystem ---------- */
.pills { display: flex; flex-wrap: wrap; gap: 7px; margin-bottom: 26px; }
.pill {
  border: 1px solid var(--line); background: #fff; padding: 4px 12px;
  font-family: var(--font-mono); font-size: 11.5px; color: var(--muted);
}
.pill b { color: var(--ink); font-weight: 700; }
table { width: 100%; border-collapse: collapse; font-size: 13.5px; border: 1px solid var(--ink); background: #fff; }
th, td { text-align: left; padding: 11px 14px; border-bottom: 1px solid var(--line); vertical-align: top; }
th {
  color: var(--ink); font-family: var(--font-mono); font-weight: 700; font-size: 10.5px;
  letter-spacing: 0.12em; text-transform: uppercase; border-bottom: 1px solid var(--ink);
}
td:first-child { font-weight: 700; }

/* ---------- quote ---------- */
.quote { padding: 80px 24px; text-align: center; }
.quote blockquote {
  font-family: var(--font-display); font-size: clamp(21px, 2.8vw, 33px);
  line-height: 1.4; max-width: 880px; margin: 0 auto; position: relative;
}
.quote blockquote::before, .quote blockquote::after {
  font-family: var(--font-display); color: var(--green-deep); font-size: 1.5em; line-height: 0;
  vertical-align: -0.3em; padding: 0 0.08em;
}
.quote blockquote::before { content: "\201C"; }
.quote blockquote::after { content: "\201D"; }
.quote .who { font-family: var(--font-mono); font-size: 11px; letter-spacing: 0.16em; text-transform: uppercase; color: var(--muted); margin-top: 22px; }

/* ---------- roadmap ---------- */
.tier { border-left: 1px solid var(--ink); padding: 4px 0 4px 26px; margin-bottom: 30px; position: relative; }
.tier::before {
  content: ""; position: absolute; left: -6px; top: 7px;
  width: 10px; height: 10px; background: var(--green); border: 1px solid var(--ink);
}
.tier h3 { font-family: var(--font-display); font-weight: 400; font-size: 21px; }
.tier .scope { font-family: var(--font-mono); color: var(--green-deep); font-size: 11px; letter-spacing: 0.1em; text-transform: uppercase; }
.tier ul { margin-top: 8px; padding-left: 20px; color: var(--muted); font-size: 14px; }
.tier li { margin: 5px 0; }
.tier li b { color: var(--ink); }

/* ---------- footer ---------- */
footer { background: var(--ink); color: var(--faint); margin-top: 0; padding: 52px 24px 60px; }
.foot-inner { max-width: 1200px; margin: 0 auto; font-size: 13.5px; }
.foot-mark {
  font-family: var(--font-display); font-size: clamp(26px, 3.6vw, 42px);
  color: var(--dark-text); line-height: 1.1; margin-bottom: 28px;
}
.foot-mark b { color: var(--green); font-weight: 400; }
.foot-inner a { color: var(--dark-text); text-decoration-color: var(--green); }
.foot-inner a:hover { background: rgba(43,238,75,0.18); }
.foot-inner ul { padding-left: 20px; margin-top: 8px; }
.foot-fine { margin-top: 22px; font-family: var(--font-mono); font-size: 11.5px; color: var(--faint); border-top: 1px solid var(--dark-line); padding-top: 18px; }

/* ---------- FAQ ---------- */
.faq { border: 1px solid var(--ink); background: #fff; }
.faq details { border-bottom: 1px solid var(--line); }
.faq details:last-child { border-bottom: none; }
.faq summary {
  list-style: none; cursor: pointer; padding: 17px 22px;
  font-family: var(--font-display); font-weight: 400; font-size: 20px; line-height: 1.32;
  display: flex; justify-content: space-between; align-items: baseline; gap: 18px;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after { content: "+"; font-family: var(--font-mono); color: var(--green-deep); font-size: 20px; flex: none; }
.faq details[open] summary::after { content: "−"; }
.faq summary:hover { background: var(--paper); }
.faq summary:focus-visible { outline: 2px solid var(--green-deep); outline-offset: -2px; }
.faq .ans { padding: 0 22px 19px; color: var(--muted); font-size: 14.5px; max-width: 880px; }